Anti-ovine Prolactin Research Articles

Inhibition of Prostatic Growth in Rabbits with Antiovine Prolactin Serum

Inhibition of Prostatic Growth in Rabbits with Antiovine Prolactin Serum

Immunochemical studies with prolactin-like fractions of fish pituitaries

A series of fractions of frozen pituitaries of the carp, Cyprinus carpio L. and the pollack, Pollachius virens L. have been prepared and the methods of extraction given. Immunochemical cross precipitin reactions have been carried out using rabbit antiovine Prolactin and antiovine growth hormone sera to determine the presence or absence of the corresponding hormones in the piscine pituitary fractions. Antipiscine prolactin sera were also obtained in rabbits using partially purified fractions of the pituitaries of the carp (FCa 719-D) and of the pollack (Fp 802-A) as antigens. It was demonstrated that antibody to piscine Prolactin will precipitate with highly purified ovine Prolactin. Using the amount of antigen at antigen-antibody equivalence zone as a point of comparison with earlier preparations, it has been possible to show that in preparation (Fp 878-A) of piscine prolactinn an approximate fivefold step in purification has been achieved. Although preliminary assays of the piscine prolactins by the freshwater survival test in hypophysectomized Fundulus heteroclitus L. indicate that these piscine pituitary fractions may not be biologically active, the precipitin reaction with antiovine Prolactin serum and fish Prolactin as well as the precipitin reaction between antipiscine Prolactin serum and ovine Prolactin suggests that there might be a common structural relationship between the prolactins of phylogenetically widely diverse origins.

The use of immunochemical binding and sephadex filtration in procedures toward the purification of ovine and piscine “prolactin”

The precipitin complex formed by antiovine Prolactin serum and the homologous antigen was dissociated in glycine-HCI buffer at pH 2.3 and the two antigenic components separated from each other by passage through a Sephadex G-100 column. Aliquots of the effluent tested immunochemically showed that the unretarded antibody was recovered first, followed by the antigen that was retarded. In order to quantitate the results obtained with ovine Prolactin radioactive iodine ( 1311) was added as a tracer to 1 mg of ovine Prolactin and precipated in 9 ml of serum and the above fractionation repeated. The recovered fractions, subjected to bioassay and immunoassay showed the separation of active ovine Prolactin from the serum proteins. Crude fish “Prolactin,” extracted from the frozen pituitaries of pollack, was precipitated with antiserum to ovine Prolactin, the precipitate dissociated and separated as above. Again immunochemical studies showed that the unretarded antibody was recovered first followed by the greatly retarded antigen. The fish “prolactin” fractions were assayed solely by immunochemical methods. Similar results were obtained with ovine growth hormone and homologous antiserum. Electrophoretic studies in polyacrylamide gels showed that the separated antigen appears as a single band in the case of both ovine and piscine “prolactin” and that they migrate at a rate similar to biologically active ovine prolactin.

Localization of prolactin within the pituitary of a cyprinodont fish, Fundulus heteroclitus (Linnaeus), by specific fluorescent antiovine prolactin globulin

Precipitin reactions in vitro have shown that antibody to ovine prolactin is capable of binding ovine prolactin and a prolactin-like fraction prepared from the pituitary glands of the carp ( Cyprinus carpio) and the pollack ( Pollachius virens). It seems reasonable to postulate that it would also bind prolactin of other teleosts. Hence the globulin fraction of antiovine prolactin serum was bound to fluorescein isothiocyanate, purified, and the antibody solution used to localize prolactin within sections of frozen pituitary of Fundulus heteroclitus. Sections so prepared show the presence of green fluorescent antigen-antibody complex only in the acidophils of the rostral pars distalis. Control staining with fluorescent normal globulin failed to give this result. Serial sections adjacent to the fluorescent antibody-treated preparaions were stained histologically and the erythrosinophilic eta cells identified as those which contain prolactin. Since no other cells of the pituitary gave these reactions it can be concluded that the eta cells are the prolactin cells. Similar preparations from the pituitaries of fresh water adapted fundulus show that in the enlarged rostral zone the erythrosinophilic eta cells contain prolactin.